BIOMETRIC INFORMATION CORRECTION APPARATUS, BIOMETRIC INFORMATION CORRECTION METHOD AND COMPUTER-READABLE RECORDING MEDIUM FOR BIOMETRIC INFORMATION CORRECTION

• US 20140133711A1
• Filed: 10/30/2013
• Published: 05/15/2014
• Est. Priority Date: 11/14/2012
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: ABE, Narishige
• Granted Patent: US 9,202,104 B2
• Time in Patent Office: Days
• US Class Current: 382/115
• CPC Class Codes: G06V 10/993 Evaluation of the quality of the acquired pattern
• CPC Class Codes: G06V 40/1347 Preprocessing; Feature extraction

Abstract

A biometric information correction method includes applying a correction process with respect to a first biometric image representing biometric information of a user to enhance a degree of clarity of the biometric information of the user, thereby creating a second biometric image, extracting a first feature amount representing features of the biometric information from the first biometric image and a second feature amount representing features of the biometric information from the second biometric image, calculating a degree of change representing a difference between the first feature amount and the second feature amount, and outputting the first feature amount when the degree of change indicates that an artifact has been created in the second biometric image.

Claims

1. A biometric information correction apparatus comprising:

a processor configured to;

apply a correction process with respect to a first biometric image representing biometric information of a user to create a second biometric image,

extract a first feature amount representing features of the biometric information from the first biometric image and a second feature amount representing features of the biometric information from the second biometric image,

calculate a degree of change representing a difference between the first feature amount and the second feature amount, and

output the first feature amount when the degree of change indicates that an artifact has been created in the second biometric image.

2. The biometric information correction apparatus according to claim 1, wherein the processor is configured to:

calculate a quality value representing quality of the biometric information on the second biometric image, and

output the second feature amount when the degree of change indicates that the artifact has not been created in the second biometric image and the second biometric image is utilized in a biometric authentication based on the quality value.

3. The biometric information correction apparatus according to claim 2, wherein when the degree of change indicates that the artifact has not been created in the second biometric image and the second biometric image has not been reached the quality which is used in the biometric authentication, the processor is configured to:

re-create a new second biometric image by using the second biometric image as the first biometric image based on the quality value,

extract a third feature amount representing the features of the biometric information from the re-created second biometric image,

calculate a degree of change between the second feature amount and the third feature amount, and

determine whether the second feature amount is to be output or the third feature amount is to be output based on the degree of change between the second feature amount and the third feature amount.

4. The biometric information correction apparatus according to claim 2, wherein the processor is configured to:

estimate cause of degradation of the biometric information in the first biometric image and select any one of a plurality of the correction processes according to the cause of degradation, and

apply the selected correction process with respect to the first biometric image.

5. The biometric information correction apparatus according to claim 2, wherein the processor is configured to:

calculate the quality value with respect to the first biometric image, and

make the level of correction applied to the first the biometric image higher as the quality value gradually becomes lower.

6. The biometric information correction apparatus according to claim 2, wherein when the processor determines that the degree of change indicates that the artifact has been created in the second biometric image, the processor is configured to:

make a level of the correction process lower compared with the level in a previous correction process and performs the correction process with respect to the first biometric image again to re-create the second biometric image,

re-extract the second feature amount from the re-created second biometric image, calculate a degree of change between the first feature amount and the re-extracted second feature amount, and

determine whether the first feature amount is to be output or the re-extracted second feature amount is to be output based on the re-calculated degree of change.

7. The biometric information correction apparatus according to claim 2, wherein when the processor determines that the degree of change indicates that the artifact has been created in the second biometric image, the processor is configured to:

change a type of correction process from the type of correction process in a previous correction process and performs the correction process with respect to the first biometric image again to re-create the second biometric image,

re-extract the second feature amount from the re-created second biometric image,

calculate a degree of change between the first feature amount and the re-extracted second feature amount, and

determine whether the first feature amount is to be output or the re-extracted second feature amount is to be output based on the re-calculated degree of change.

8. The biometric information correction apparatus according to claim 1, further comprising:

a storage configured to store the registered feature amount which represents the features of the biometric information extracted from a registered biometric image on which biometric information of a registered user captured;

wherein the processor is configured to;

match the feature amount against the registered feature amount to calculate a degree of similarity between the biometric information of the user and the biometric information of the registered user, and

determine whether the user is to be authenticated depending on the degree of similarity.

9. The biometric information correction apparatus according to claim 1, wherein the processor is configured to store the feature amount in the storage along with identification number of the user.

10. The biometric information correction apparatus according to claim 1, wherein the processor configured to

divide each of the first biometric image and the second biometric image into a plurality of blocks, and calculates the degree of change between the first feature amount and the second feature amount included in each of the plurality of blocks, respectively, and

output the first feature amount with respect to the block when the degree of change indicates that the artifact of the biometric information has been created in any one of the plurality of blocks of the second biometric image.

11. A biometric information correction method comprising:

applying a correction process with respect to a first biometric image representing biometric information of a user to enhance a degree of clarity of the biometric information of the user, thereby creating a second biometric image;

extracting a first feature amount representing features of the biometric information from the first biometric image and a second feature amount representing features of the biometric information from the second biometric image;

calculating a degree of change representing a difference between the first feature amount and the second feature amount; and

outputting the first feature amount when the degree of change indicates that an artifact has been created in the second biometric image.

12. The biometric information correction method according to claim 11, further comprising:

calculating a quality value representing quality of the biometric information on the second biometric image; and

outputting the second feature amount when the degree of change indicates that the artifact has not been created in the second biometric image and the second biometric image is utilized in a biometric authentication based on the quality value.

13. The biometric information correction method according to claim 12, further comprising:

re-creating a new second biometric image by using the second biometric image as the first biometric image based on the quality value, when the degree of change indicates that the artifact has not been created in the second biometric image and the second biometric image has not been reached the quality which is used in the biometric authentication;

extracting a third feature amount representing the features of the biometric information from the re-created second biometric image;

calculating a degree of change between the second feature amount and the third feature amount; and

determining whether the second feature amount is to be output or the third feature amount is to be output based on the degree of change between the second feature amount and the third feature amount.

14. A computer-readable recording medium storing a computer program that, when executed, causes a computer to execute a biometric information correction method comprising:

applying a correction process with respect to a first biometric image representing biometric information of a user to enhance a degree of clarity of the biometric information of the user, thereby creating a second biometric image;

extracting a first feature amount representing features of the biometric information from the first biometric image and a second feature amount representing features of the biometric information from the second biometric image;

calculating a degree of change representing a difference between the first feature amount and the second feature amount; and

outputting the first feature amount when the degree of change indicates that the artifact has been created in the second biometric image.